Fertilizer Basics: Essential Nutrients for Healthy Plants

Don't let your plants go hungry

Less than half of home gardeners use fertilizer, missing out on more flowers, higher yields, and better disease resistance. Well-fed plants are healthier, more productive, and more beautiful.

Plant Nutrients 101

Plants need six primary nutrients. Carbon, hydrogen, oxygen come from air and water. The other three—nitrogen (N), phosphorus (P), potassium (K)—must come from soil.

• Nitrogen: Promotes leafy growth; excess reduces flowering/fruiting.
• Phosphorus: Stimulates roots, buds, flowers, seeds; needs pH 6.5–6.8 for uptake.
• Potassium: Improves vigor, carbohydrate production, disease resistance.

Secondary nutrients: calcium, magnesium, sulfur. Micronutrients (boron, copper, iron, etc.) needed in tiny amounts.

Organic vs. Synthetic Fertilizers

• Organic: Slow-release, improve soil structure, stimulate microbes, best applied in fall.
• Synthetic: Fast-acting, water-soluble, can burn plants, leach into waterways.

For long-term soil health, build fertility with organic fertilizers and compost. Supplement with water-soluble fertilizer during active growth.

Foliar Feeding & pH

Foliar sprays absorb nutrients 8–20x more efficiently than roots—ideal at transplanting, blooming, and fruit set. Soil pH (ideally 6.0–7.0) affects nutrient availability; test and adjust gradually with lime or sulfur.

Choosing a Fertilizer

All-purpose 5-5-5 works for most plants. The N-P-K ratio shows percentage by weight. Organic ratios appear lower because only immediately available nutrients count. Select based on soil test and plant needs.

Slow-release organic tomato fertilizer (5-6-5) for abundant fruit.